Label-free multimodal coherent anti-Stokes Raman scattering analysis of microparticles in unconstrained microfluidics.

Fast, label-free optical identification and quantification of biomolecules and other relevant biological materials in microfluidic devices and the vascular system will play a major role in liquid biopsy and related diagnoses. An optical microscope probing simultaneously non-linear coherent anti-Stokes Raman scattering (CARS) and linear scattering (LS) was used to probe microparticles in aqueous solutions flowed unconstrained in microfluidic channels. Despite the optical complexity of these systems, where out-of-focus microparticles randomly impede CARS and LS, and where water CARS generates a substantial background, we demonstrate that in-focus microparticles can be individually and unambiguously detected when CARS and LS are co-analyzed. The ability to chemically discriminate microscale features in optically realistic flows supports the relevance of multimodal CARS platforms for liquid biopsy.

A quantitative review of MHC-based mating preference: the role of diversity and dissimilarity.

Sexual selection hypotheses stipulate that the major histocompatibility complex genes (MHC) constitute a key molecular underpinning for mate choice in vertebrates. The last four decades saw growing empirical literature on the role of MHC diversity and dissimilarity in mate choice for a wide range of vertebrate animals, but with mixed support for its significance in natural populations. Using formal phylogenetic meta-analysis and meta-regression techniques, we quantitatively review the existing literature on MHC-dependent mating preferences in nonhuman vertebrates with a focus on the role of MHC diversity and dissimilarity. Overall, we found small, statistically nonsignificant, average effect sizes for both diversity- and dissimilarity-based mate choice (r = 0.113 and 0.064, respectively). Importantly, however, meta-regression models revealed statistically significant support regarding female choice for diversity, and choice for dissimilarity (regardless of choosy sex) only when dissimilarity is characterized across multiple loci. Little difference was found among vertebrate taxa; however, the lack of statistical power meant statistically significant effects were limited to some taxa. We found little sign of publication bias; thus, our results are likely to be robust. In light of our quantitative assessment, methodological improvements and fruitful future avenues of research are highlighted.

Does surgical approach influence component positioning with Birmingham Hip Resurfacing?

The aim of this study was to compare the component positioning of Birmingham Hip Resurfacings implanted through a posterolateral approach with those inserted via a direct lateral approach. Sixty-four hip resurfacings for osteoarthritis were carried out by a single surgeon: 23 through a direct lateral approach and 41 through a posterolateral approach. No significant differences in implant survival, Oxford Hip Scores or complications were found. The mean abduction angle for the acetabular component was lower (p < 0.007) with a posterior approach (mean: 37.5 degrees ; range 26-50 degrees ) than the lateral approach (mean: 43 degrees ; range 30-56 degrees ). There was no significant difference in stem orientation, either in flexion/extension or varus/valgus, between the two groups. This study demonstrates that components can be implanted in an acceptable orientation through either approach but that the posterior approach results in greater closure of the acetabular component.

Sensing of water dissolved in solvents using a 5.629 microm multimode quantum cascade laser.

We report herein the detection of liquid water dissolved in a variety of solvents using a thermoelectrically cooled, pulsed, Fabry-Perot quantum cascade laser, operating at 5.629 microm at room temperature. The prototype sensor system consisted of the laser, a series of off-axis parabolic mirrors, and two mercury cadmium telluride detectors. When applied to the detection of water in tetrahydrofurane, a limit of detection of 0.85 parts per million was achieved. It is envisaged that such a sensor would be well suited to process control applications within the pharmaceuticals industry.

Exeter-Ogee total hip replacement using the Hardinge approach; the ten to twelve year results.

We reviewed 131 consecutive primary total hip replacements implanted into 127 patients between 1995 and 1997. Surgery was performed through a Hardinge approach using the Exeter universal stem in combination with the Ogee Elite acetabular component.Five of 131 hips have required revision. The ten year survival analysis demonstrates: 95.3% survival with revision for any cause as the end point; 98.9% with revision for aseptic loosening of the stem as the endpoint, 98.1% revision for aseptic loosening of the acetabular component as the endpoint. There were no cases of dislocation.Our findings show that the Exeter universal stem in combination with the Ogee Elite acetabular component can be inserted through a Hardinge approach in a district general setting with results comparable to surgery performed in a specialist unit and through a posterior approach.

Medial epicondylitis of the elbow.

Ninety-five cases of medial epicondylitis are reported in 83 patients; 90% were related to work and only 10% to sport or leisure activities. Most recovered with conservative treatment. Operation was needed in 12%, which compared with under 4% of patients with lateral epicondylitis over the same period. The results of open release of the common flexor origin were good, with only one exception.

Intramedullary nailing technique and its effect on union rates of tibial shaft fractures.

Seventy tibial shaft fractures treated by intramedullary nailing using two different techniques were compared. The first group (35 cases) was treated with a Herzog intramedullary nail following hand reaming and minimal traction. The second group (35 cases) had a Grosse and Kempf or AO nail inserted following power reaming and skeletal traction. Fracture patterns were similar in both groups. In the hand-reamed group, the mean time to union was 15.2 weeks with two delayed unions and no non-unions. In the power-reamed group, the mean time to union was 19.9 weeks with 10 delayed unions and two non-unions. These differences were statistically significant. Complications in the hand-reamed group included a Sudecks atrophy and one mal-union. In the power-reamed group, there were three transient foot drops, two compartment syndromes and one pulmonary embolus. This difference was not statistically significant. Our findings suggest that surgical technique has an important effect on the healing rates of nailed tibial shaft fractures. When intramedullary nailing is performed, minimal reaming is required and skeletal traction should be avoided if possible.

Scaphoid exostosis causing rupture of the flexor pollicis longus.

A case of attrition rupture of the flexor pollicis longus (FPL) tendon caused by a scaphoid osteophyte in a patient with rheumatoid arthritis is reported. This lesion was found only after a thorough search of the floor of the carpal tunnel was performed.

Tibial shaft fractures with an intact fibula.

The effect of several factors on the healing rates of tibial shaft fractures with an intact fibula were examined. Those found to adversely affect healing rates included: 1. Open fractures; 2. Oblique or comminuted fractures; 3. High-velocity injuries; 4. Angulation in the sagittal plane; 5. Displacement. No other factors examined were associated with delayed union. The predictive values for delayed union are estimated for each of these factors in isolation and in combination.

Tibial plateau fractures: the arthroscopic option.

Tibial plateau fractures remain one of the most difficult fractures to treat. A multitude of classifications exist and several treatment options have been advocated. In the last few years arthroscopy has been used in the treatment of these fractures. We report our experience of treating over 30 cases by this method and review the literature.

The effect of high-intensity trunk exercise on bone mineral density of postmenopausal women.

The purpose of this study was to determine the effect of a 1-year trunk resistive exercise program on bone mineral density at the lumbar spine and hip in postmenopausal women. Forty-nine subjects were divided into exercise and control groups. Dual photon absorptiometry was used to measure bone mineral density and the Muscle Examination and Exercise Dosimeter 3000 system was used to assess trunk muscle strength. Resistive exercise target levels for the exercise group were based on the results of the trunk muscle strength tests. The exercise group performed 3 sets of 10 repetitions for each of the sit-up, prone trunk extension, and double leg flexion exercises. The subjects were seen once per month and performed the exercises a minimum of three times per week. The bone mineral density and strength tests were done at baseline, at 6 months and at 12 months. The results of the study showed that 1) the dual photon absorptiometry method and the Muscle Examination and Exercise Dosimeter 3000 system were highly reliable in measuring bone mineral density and trunk muscle strength, respectively; and 2) no significant differences were found between the exercise and control groups at lumbar vertebrae L2, L3, L4, L2-L4, and the femoral neck, Ward's triangle, and trochanteric region of the proximal femur at baseline, 6-month, and 12-month evaluation sessions.

The Exeter bipolar prosthesis in the active elderly patient: the results at 7 years.

Seventy one Exeter bipolar hemiarthroplasties were reviewed after a mean follow up of 3.2 years (range 1-7 years). Patients with displaced subcapital fractures were selected for operation on the basis of good mobility before the fracture. The operation was well tolerated and the mortality at 1 month and 6 months was 3.7% and 6.5% respectively. Using a newly devised hip scoring system 89% had a good or excellent result and 94% had no or only occasional pain. There was no radiological evidence of acetabular erosion.

Arthroscopic management of tibial plateau fractures.

Ten tibial plateau fractures treated arthroscopically are reported. In eight cases, closed internal fixation was performed under arthroscopic control while in another two patients, arthroscopic washout alone was undertaken. Only one case required external splintage (a cast brace), the remainder being mobilized non-weight-bearing without plaster immediately after the operation. The results were good. We suggest that the arthroscope is a useful tool in the treatment of these fractures and provides information not otherwise available. There is a low morbidity, inpatient stay is short and early joint movement can be encouraged.

The intact fibula.

The notes and radiographs of 281 adult tibial shaft fractures were reviewed. In 17 per cent there was an intact fibula. Delayed union rates were lower when the fibula remained intact, thus confirming that this is a good prognostic indicator. This fracture is caused by less severe trauma than fractures where both bones are broken. It is rare over the age of 30 years.

Corrective tibial osteotomy for genu recurvatum by callus distraction using an external fixator.

Genu recurvatum due to an osseous abnormality is a condition that rarely requires surgical intervention. When necessary, the operative solution usually considered is an opening wedge osteotomy using bone graft and plate fixation. The donor site (usually the iliac crest) has a well reported morbidity with a further procedure being required to remove the plate. We report two cases treated by a hemicorticotomy and callus distraction (hemicallotasis) of the tibia using an external fixator. Correction was performed under supervision as an out-patient. Hospital stay was short, the morbidity of the donor site was eliminated, further procedures for removal of the plate were unnecessary and mobility of both the patient and his joints was maintained throughout the period of treatment. Satisfactory correction of the deformity was obtained in both cases.

Proximal tibio-fibular synostosis. A rare congenital anomaly.

A case of proximal tibiofibular synostosis is presented along with a review of the literature. The variety of presenting complaints is discussed and the syndrome is compared with that of radio-ulnar synostosis. Possible modes of treatment are explained.

The effect of trunk resistive exercise on muscle strength in postmenopausal women.

At the time this study was conducted. Ms. O'Dwyer and Ms. Lin were physical therapy master's degree students. Dr. Blanpied was a doctoral student. This paper was presented at the First International Orthopaedic Symposium in Ottawa, Canada, in May, 1990. This study was supported by Grant RR59 from the General Clinical Research Centers Program, Division of Research Resources, NIH, and by an Aging Seed Grant from The University of Iowa.Fifty-five women with an average age of 56 years participated in a study to determine the effects of a quantitatively based home exercise program on trunk muscle strength. The same body positions were used for testing trunk strength and for the exercise program. During the strength tests, the external forces generated by the subjects were measured using the trunk attachment of the Muscle Evaluation and Exercise Dosimeter (MEED) 3000 System. The standardized exercise program utilized the body segments and cuff weights on the extremities to achieve the desired resistance level for the sit-up, prone trunk extension, and double-leg flexion exercises. Three sets of 10 were performed for each exercise at least three times a week over a 12-month period. Large, significant (p < .05) strength gains (25-30%) were made by the exercise group for each exercise. The performance of the exercise group was superior to the control group. The reliability of the strength-using tests determined by interday trials using the MEED 3000 was high-all correlations were r = .93 or higher. This study demonstrates that older women can tolerate and increase trunk muscle strength using controlled, progressive, resistive exercise over a long period of time. The exercise approach in this study might be considered for use in treatment of low back dysfunction. J Orthop Sports Phys Ther 1991;13(6):300-309.

Relationship between trunk muscle torque and bone mineral content of the lumbar spine and hip in healthy postmenopausal women.

The purpose of the study was to determine the relationship between trunk muscle strength and bone mineral density (BMD). Fifty-six postmenopausal women, aged 38 to 73 years, were examined. The BMD of lumbar vertebrae L2-4, the femoral neck, the Ward's triangle, and the greater trochanter was measured with dual-photon absorptiometry. Isometric and isokinetic torque and work measurements obtained on a trunk testing unit were used to assess trunk flexor and extensor strength. Correlation analysis demonstrated a statistically significant relationship between most trunk torque and work measurements and BMD. The trunk extensors generally provided higher correlations with BMD than did the trunk flexors, and the isokinetic extension torque values demonstrated higher correlations than the isometric extension values in every case. Linear backward-regression models, based on the subjects' weight and trunk flexor and extensor torque and work measurements, demonstrated multiple-correlation coefficients of .67, .58, .43, and .65 in predicting the BMD of the L2-4 region, femoral neck, Ward's triangle, and greater trochanter region, respectively. Estrogen therapy status did not affect the linear regression models. These data suggest a positive relationship in postmenopausal women between flexor and extensor torque values and BMD at the lower lumbar spine and proximal femur.